Tag Archives: Pinhole Projection

The weather forecast is, as is often the case, not on our side for this particular event, but those with solar observing equipment may be able to take in a “hybrid” solar eclipse this Sunday morning, November 3rd, from sunrise (6:42 a.m.) to 8:00 a.m.

And don’t forget that we switch our clocks back to Standard Time on Sunday. You’ve an extra hour to get your equipment ready!

The timing and placement of the Moon between ourselves and the Sun will be producing a proper total eclipse only briefly (Sky & Telescope says “seconds” for a perfectly-placed observer) and not near us, but the Sun will rise as a crescent as the New Moon takes a significant chunk out of it. I made a series of still images with Starry Night Pro below to show both how much of the Sun’s disc will be blocked by the black disc of the New Moon and how quickly the entire event will occur (6:42 a.m. being sunrise for Syracuse, NY – the entire event will be done by about 8:00 a.m.).

The hybrid solar eclipse from Syracuse (images using Starry Night Pro). Click for a larger version.

And what is a “hybrid” solar eclipse anyway? We’re all familiar with the “total eclipse,” where the Moon and Sun have the same (or nearly the same) apparent diameter in the sky – this blocking of the Sun’s surface is what allows us to see the wispy corona that is otherwise washed out by the Sun’s surface brightness. An “annular eclipse” is the lesser cousin of the total eclipse, where the Moon in its orbit is farther away from Earth than it would be in a total eclipse, meaning it appears slightly smaller in the sky – as it no longer has the apparent diameter of the Sun, the Moon does not cover it completely, producing a sharp solar ring. A “partial eclipse” is where the Moon makes a “grazing blow” of the Sun, producing solar crescents (which may be very sharp crescents or may just slide along one side of the Sun, producing rounded PacMan views).

The “hybrid eclipse” is called so because certain places on the Earth’s surface see an annular eclipse, while others see, perhaps only very briefly, a total eclipse. Timing and location are everything, making hybrid eclipses quite rare (the number I’ve seen quoted at a few sites is 5% of all eclipses are hybrid).

The Sun will still be plenty bright enough to damage your eyes after sunrise – this will most definitely NOT be one of those eclipses that lets you enjoy a view of the Sun without filters or special optics. Pinhole projectors or a pair of Baader glasses will work just fine. A good how-to page for building your own pinhole solar projector can be found at solar-center.stanford.edu/observe/.

And if the weather does not cooperate Sunday morning, you can always watch the eclipse real-time thanks to the Slooh Community Observatory feed (events.slooh.com).

Several good links on the subject are below. You can be an expert to your very groggy friends on Sunday in less than 15 minutes.